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United States Patent | 5,558,347 |
Nicholson | September 24, 1996 |
A static seal comprising an envelope of chemically resistant PTFE and a metallic packing ring within the envelope shaped to form cells. The cells may be filled with an inert gas under pressure so that increased loads on the seal may be cushioned.
Inventors: | Nicholson; Terence P. (Hexham, GB3) |
Assignee: | Specialist Sealing Limited (Jersey, GB1) |
Appl. No.: | 427881 |
Filed: | April 26, 1995 |
Dec 31, 1990[GB] | 9028219 | |
Jan 21, 1991[GB] | 9101301 |
Current U.S. Class: | 277/652; 277/946 |
Intern'l Class: | F16J 015/00 |
Field of Search: | 277/207 R,207 A,211,213,215,235 B,236,34,34.3,209,229,233,235 R,235 A |
1160316 | Nov., 1915 | Paterson | 277/235. |
1731404 | Oct., 1929 | Wetherill | 277/207. |
2156662 | May., 1939 | Wills | 277/235. |
2580546 | Jan., 1952 | Hobson, Jr. | |
2888540 | Mar., 1954 | Gratzmuller | 200/151. |
3332566 | Jul., 1967 | Phillips | 277/213. |
3817540 | Jun., 1974 | Nicholson | 277/236. |
4451051 | May., 1984 | Nicholson | 277/236. |
4711456 | Dec., 1987 | Udagawa | 277/235. |
4795174 | Jan., 1989 | Whitlow | 277/213. |
4948153 | Aug., 1990 | Takahashi | 277/236. |
Foreign Patent Documents | |||
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2828475 | Jan., 1980 | DE | . |
3720224 | Jan., 1989 | DE | . |
0285644 | Nov., 1989 | JP | 277/235. |
1213454 | Nov., 1970 | GB | . |
1273136 | May., 1972 | GB | . |
1527344 | Oct., 1978 | GB | . |
2097872 | Apr., 1985 | GB | . |
2229047 | Sep., 1990 | GB. | |
2210939 | May., 1991 | GB. | |
2246822 | Feb., 1992 | GB | . |
WO8903491 | Apr., 1989 | WO | . |